Hydrangea plant named ‘Hortmacaro’

ABSTRACT

A new and distinct cultivar of  Hydrangea  plant named ‘Hortmacaro’, characterized by its upright and spreading plant habit; moderately vigorous to vigorous growth habit and moderate growth rate; moderate branching habit with strong and thick sturdy stems; large mophead-type inflorescences with dark red purple-colored sterile flowers; and good postproduction longevity.

Botanical designation: Hydrangea macrophylla.

Cultivar denomination: ‘HORTMACARO’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Hydrangea plant, botanically known as Hydrangea macrophylla, commercially referred to as a mophead-type Hydrangea and hereinafter referred to by the name ‘Hortmacaro’.

The new Hydrangea plant is a product of a planned breeding program conducted by the Inventor in Boskoop, The Netherlands. The objective of the breeding program was to create new Hydrangea plants with large inflorescences with numerous dark red purple-colored sterile flowers and good postproduction longevity.

The new Hydrangea plant originated from a cross-pollination made by the Inventor in May, 2009 in Boskoop, The Netherlands, of a proprietary selection of Hydrangea macrophylla identified as code number 07-071-02, not patented, as the female, or seed, parent with a proprietary selection of Hydrangea macrophylla identified as code number 08-025-01, not patented, as the male, or pollen, parent. The new Hydrangea plant was discovered and selected by the Inventor as a single flowering plant from within the progeny of the stated cross-pollination in a controlled greenhouse environment in Boskoop, The Netherlands in June, 2011.

Asexual reproduction of the new Hydrangea plant by vegetative terminal cuttings in a controlled environment in Boskoop, The Netherlands since 2011 has shown that the unique features of this new Hydrangea plant are stable and reproduced true to type in successive generations.

SUMMARY OF THE INVENTION

Plants of the new Hydrangea have not been observed under all possible combinations of environmental conditions and cultural practices. The phenotype may vary somewhat with variations in environmental conditions such as temperature and light intensity without, however, any variance in genotype.

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘Hortmacaro’. These characteristics in combination distinguish ‘Hortmacaro’ as a new and distinct Hydrangea plant:

-   -   1. Upright and spreading plant habit.     -   2. Moderately vigorous to vigorous growth habit and moderate         growth rate.     -   3. Moderate branching habit with strong and thick sturdy stems.     -   4. Large mophead-type inflorescences with dark red         purple-colored sterile flowers.     -   5. Good postproduction longevity.

Plants of the new Hydrangea can be compared to plants of the female parent selection. Plants of the new Hydrangea differ primarily from plants of the female parent selection in sterile flower color as sterile flower sepals of plants of the new Hydrangea are lighter red purple in color than sterile flower sepals of plants of the female parent selection. In addition, margins of sterile flower sepals of plants of the new Hydrangea are serrate and undulate whereas margins sterile flower sepals of plants of the female parent selection are entire and slightly undulate.

Plants of the new Hydrangea can be compared to plants of the male parent selection. Plants of the new Hydrangea differ primarily from plants of the male parent selection in branching habit as plants of the new Hydrangea are not as freely branching as plants of the male parent selection. In addition, margins of sterile flower sepals of plants of the new Hydrangea are serrate and undulate whereas margins sterile flower sepals of plants of the male parent selection are entire and slightly undulate.

Plants of the new Hydrangea can be compared to plants of the Hydrangea macrophylla ‘Magical Opal’, disclosed in U.S. Plant Pat. No. 20,483. In side-by-side comparisons plants of the new Hydrangea differ primarily from plants of ‘Magical Opal’ in the following characteristics:

-   -   1. Plants of the new Hydrangea are not as freely branching as         plants of ‘Magical Opal’.     -   2. Plants of the new Hydrangea have larger sterile flower sepals         than plants of ‘Magical Opal’.     -   3. Sterile flower sepals of plants of the new Hydrangea are         curly and serrate whereas sterile flower sepals of plants of         ‘Magical Opal’ are mostly flat with entire margins.

Plants of the new Hydrangea can be compared to plants of the Hydrangea macrophylla ‘Magical Emerald’, disclosed in U.S. Plant Pat. No. 20,464. In side-by-side comparisons plants of the new Hydrangea differ primarily from plants of ‘Magical Emerald’ in the following characteristics:

-   -   1. Plants of the new Hydrangea are more freely branching than         plants of ‘Magical Emerald’.     -   2. Plants of the new Hydrangea have darker red purple sterile         flower sepals than plants of ‘Magical Emerald’.     -   3. Sterile flower sepals of plants of the new Hydrangea are         curly and serrate whereas sterile flower sepals of plants of         ‘Magical Emerald’ are flat with entire margins.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying colored photographs illustrate the unique appearance of the new Hydrangea plant showing the colors as true as it is reasonably possible to obtain in colored reproductions of this type. Colors in the photographs may differ from the color values cited in the detailed botanical description which accurately describe the colors of the new Hydrangea plant.

The photograph on the first sheet is a side perspective view of a typical flowering plant of ‘Hortmacaro’ grown in a container.

The photograph on the second sheet is a close-up view of a typical inflorescence of ‘Hortmacaro’.

DETAILED BOTANICAL DESCRIPTION

Plants used in the aforementioned photographs and in the following description were grown during the summer in 17-cm containers in a glass-covered greenhouse in Boskoop, The Netherlands and under cultural practices typical of commercial Hydrangea production. During the production of the plants, day temperatures ranged from 16° C. to 30° C. and night temperatures ranged from 10° C. to 18° C. Plants of the new Hydrangea were two years old when the photographs and description were taken. Plants of the new Hydrangea are not typically treated with aluminum sulfate to “blue” the inflorescences. In the following description, color references are made to The Royal Horticultural Society Colour Chart, 2015 Edition, except where general terms of ordinary dictionary significance are used.

-   Botanical description: Hydrangea macrophylla ‘Hortmacaro’. -   Parentage:     -   -   Female, or seed, parent.—Proprietary selection of Hydrangea             macrophylla identified as code number 07-071-02, not             patented.         -   Male, or pollen, parent.—Proprietary selection of Hydrangea             macrophylla identified as code number 08-025-01, not             patented. -   Propagation:     -   -   Type cutting.—By vegetative terminal cuttings.         -   Time to initiate roots, summer.—About three weeks at             temperatures about 15° C. to 25° C.         -   Time to produce a rooted young plant, summer.—About six             weeks at temperatures about 15° C. to 25° C.         -   Root description.—Medium in thickness, fibrous; typically             creamy white in color, actual color of the roots is             dependent on substrate composition, water quality,             fertilizer type and formulation, substrate temperature and             physiological age of roots.         -   Rooting habit.—Moderately freely branching; medium density. -   Plant description:     -   -   Plant and growth habit.—Upright and spreading plant habit;             inverted triangle in shape; strong and sturdy lateral             branches; moderate growth rate and moderately vigorous to             vigorous growth habit.         -   Plant height.—About 47.2 cm.         -   Plant diameter or area of spread.—About 50 cm. -   Lateral branch description:     -   -   Branching habit.—Moderate branching habit; when pinched,             about five lateral branches develop per plant.         -   Length.—About 32.1 cm.         -   Diameter.—About 7.5 mm.         -   Internode length.—About 9.9 cm.         -   Texture.—Smooth, glabrous; fully developed, woody.         -   Aspect.—Upright to about 15° from vertical.         -   Strength.—Strong, sturdy.         -   Color.—When developing: Close to 144A. Developed: Close to             144A to 144B; at the internodes, tinged with close to N186C;             when woody, close to N199A and N200B to N200C.         -   Lenticels.—Not observed. -   Leaf description:     -   -   Arrangement.—Opposite, simple.         -   Length.—About 12.9 cm.         -   Width.—About 10.6 cm.         -   Shape.—Broadly ovate.         -   Apex.—Apiculate.         -   Base.—Short attenuate to somewhat obtuse.         -   Margin.—Coarsely serrate.         -   Texture, upper surface.—Smooth to slightly rugose, glabrous.         -   Texture, lower surface.—Smooth to moderately rugose, mostly             glabrous, sparsely pubescent along venation.         -   Venation pattern.—Pinnate.         -   Color.—Developing leaves, upper surface: Darker than between             137A and 143A. Developing leaves, lower surface: Close to             between 146B and 146C. Fully expanded leaves, upper surface:             Close to 137A; venation, close to N148C. Fully expanded             leaves, lower surface: Close to 146B; venation, close to             145C.         -   Petioles.—Length: About 2.3 cm. Diameter: About 4.5 mm.             Texture and luster, upper surface: Smooth, glabrous; matte.             Texture and luster, lower surface: Smooth, glabrous;             slightly glossy. Color, upper surface: Close to 145B. Color,             lower surface: Close to 144B. -   Flower description:     -   -   Flower type and habit.—Showy sterile flowers and small             inconspicuous fertile flowers arranged on mophead-type             terminal panicles; panicles flattened globular in shape;             fertile flowers face mostly upright and sterile flowers face             upright to outwardly to slightly drooping depending on their             position in the inflorescence.         -   Fragrance.—None detected.         -   Natural flowering season.—Plants flower from late spring to             late summer in The Netherlands.         -   Flower longevity.—Fertile flowers last about five days on             the plant, fertile flowers not persistent; sterile flowers             last about six weeks on the plant, sterile flowers             persistent.         -   Quantity of flowers.—Freely flowering habit; about 40             fertile flowers per panicle and about 85 sterile flowers per             panicle.         -   Panicle height.—About 10.4 cm.         -   Panicle diameter.—About 17.1 cm.         -   Fertile flower buds.—Length: About 4 mm. Diameter: About             5 mm. Shape: Flattened globular. Color: Close to 69D and 70B             to 70C; fading towards the base, close to 145D; at the base,             close to 150B.         -   Sterile flower buds.—Length: About 1.4 cm. Diameter: About             1 cm. Shape: Cup-shaped. Color: Close to 63B.         -   Fertile flower diameter.—About 9 mm.         -   Fertile flower depth (height).—About 7 mm.         -   Sterile flower diameter.—About 5.8 cm.         -   Sterile flower depth (height).—About 2.3 cm.         -   Petals, fertile flowers.—Quantity and arrangement: Six in a             single whorl. Length: About 4 mm. Width: About 2 mm. Shape:             Ovate, concave. Apex: Acute. Base: Cuneate. Margin: Entire.             Texture and luster, upper surface: Smooth, glabrous;             slightly glossy. Texture and luster, lower surface: Smooth,             glabrous; matte. Color: When opening and fully opened, upper             surface: Close to 65A to 65B; color does not fade with             development. When opening and fully opened, lower surface:             Close to 65A; color does not change with development.         -   Petals, sterile flowers.—Quantity and arrangement: About             four in a single whorl. Length: About 4 mm. Width: About             3 mm. Shape: Ovate, concave. Apex: Acute. Base: Cuneate.             Margin: Entire. Texture and luster, upper surface: Smooth,             glabrous; slightly glossy. Texture and luster, lower             surface: Smooth, glabrous; matte. Color: When opening and             fully opened, upper surface: Close to 65A to 65B; color does             not fade with development. When opening and fully opened,             lower surface: Close to 65A; color does not change with             development.         -   Sepals, fertile flowers.—Quantity and arrangement: About six             in a single whorl. Length: About 2 mm. Width: About 1.5 mm.             Shape: Ovate. Apex: Acute. Base: Broadly cuneate. Margin:             Entire. Texture and luster, upper surface: Smooth, glabrous;             matte. Texture and luster, lower surface: Smooth, glabrous;             slightly glossy. Color: When opening and fully opened, upper             surface: Close to 150B; fading towards the base to close to             145D; color does not change with development. When opening             and fully opened, lower surface: Close to 150B; fading             towards the base to close to 145D; color does not change             with development.         -   Sepals, sterile flowers.—Quantity and arrangement: Four or             occasionally five in a single whorl. Length: About 3.2 cm.             Width: About 3.8 cm. Shape: Broadly reniform to reniform.             Apex: Broadly and bluntly apiculate. Base: Cuneate. Margin:             Irregularly and coarsely crenate to serrate; moderately to             strongly undulate. Texture and luster, upper and lower             surfaces: Smooth, glabrous; matte. Color: When opening,             upper surface: Close to 63A. When opening, lower surface:             Close to 63C. Fully opened, upper surface: Close to 64D;             color does not fade with development. Fully opened, lower             surface: Close to 65A; color does not fade with development.         -   Pedicels, fertile flowers.—Length: About 2 mm. Diameter:             About 1 mm. Strength: Moderately strong. Aspect: Mostly             upright, about 10° from vertical. Texture and luster:             Sparsely pubescent; matte. Color: Close to 150D slightly             tinged with close to 63D.         -   Pedicels, sterile flowers.—Length: About 1.9 cm. Diameter:             About 2 mm. Strength: Moderately strong. Aspect: About 35°             from vertical. Texture and luster: Moderately pubescent;             matte. Color: Close to between 63C and 64D.         -   Reproductive organs, fertile flowers.—Stamens: Quantity per             flower: About twelve. Filament length: About 3 mm. Filament             color: Close to NN155D. Anther length: About 1.5 mm. Anther             shape: Oblong. Anther color: Close to 155C. Pollen amount:             Moderate. Pollen color: Close to 160C. Pistils: Pistil             quantity per flower: About three or occasionally two. Pistil             length: About 1.5 mm. Stigma shape: Club-shaped. Stigma             color: Close to NN155A. Style length: About 0.5 mm. Style             color: Close to NN155A. Ovary color: Close to N155A.         -   Reproductive organs, sterile flowers.—Stamens: Quantity per             flower: About eight. Filament length: About 2 mm. Filament             color: Close to NN155B. Anther length: About 1.5 mm. Anther             shape: Broadly oblong. Anther color: Close to 155C. Pollen             amount: Moderate. Pollen color: Close to 160C. Pistils:             Pistil quantity per flower: About three. Pistil length:             About 1.5 mm. Stigma shape: Club-shaped. Stigma color: Close             to NN155A. Style length: About 0.5 mm. Style color: Close to             NN155A. Ovary color: Close to N155A.         -   Seeds.—To date, seed development has not been observed on             plants of the new Hydrangea. -   Disease & pest resistance: Under commercial production conditions,     plants of the new Hydrangea have not been observed to be resistant     to pathogens and pests common to Hydrangea plants. -   Temperature tolerance: Plants of the new Hydrangea have been shown     to be suitable for USDA Hardiness Zones 5 to 9. 

It is claimed:
 1. A new and distinct Hydrangea plant named ‘Hortmacaro’ as illustrated and described. 